Idle Speed

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Idle speed is controlled by an idle speed control valve. Ensure engine is at normal operating temperature, valve clearance is correct and all electrical accessories are off.
Connect dwell/tachometer to engine. Ensure idle speed is within specification. See IDLE SPEED & CO LEVEL SPECIFICATIONS table. If idle speed and CO level are not within specification, check idle speed control valve or intake manifold for air leaks.

IDLE SPEED & CO LEVEL SPECIFICATIONS

Application

Idle RPM

⁽¹⁾ CO Level %

4-Cylinder

810-890

.5-.7

6-Cylinder

660-740

.2-1.2

750-850

.2-1.2

⁽¹⁾	Measured at exhaust manifold. See IDLE MIXTURE & CO LEVEL for additional information.